The ability to sinter certain materials at a low temperature is extremely important. Certain high-strength alloys of aluminum cannot be processed using conventional powder metallurgy techniques. This is due to a high sintering temperature which results in eutectic melting and/or peritectic decomposition of the alloy, forming a non-ideal two-phase structure. Furthermore, the self-passivating nature of aluminum and other alloys leads to oxides scales on powders if exposed to air, thus inhibiting sintering. Conventional powder processing techniques rely on mechanical force, e.g. pressing or extruding, to break up the oxide scale and enable consolidation.
Hydride micropowders are sometimes used in powder metallurgy applications as sintering aids, reducing agents, and/or foaming agents. These powders are mixed or milled together, often resulting in a non-uniform distribution of powders. Improvements are desired to eliminate non-uniform distribution of sintering aids.